For example, a LIN (local interconnect network) as a multi-communication protocol for a vehicle is used for receiving and transmitting a signal of a sensor, an actuator or the like. In a LIN protocol, a LIN transceiver having one channel and includes one bus activation circuit. On start-up, based on a signal such as an INHIBIT signal, an external circuit is activated. When the number of LIN busses is large, and multiple transceivers are mounted on one ECU (electric control unit), it is necessary for a CPU mounted on the ECU to recognize which transceiver executes an activation of the bus. In this case, the signal such as the INHIBIT signal may be input into a port of the CPU. Alternatively, the signal such as the INHIBIT signal may be transmitted to the CPU as a serial signal. Thus, the recognition in the CPU may be executed in various ways.
When the above constitution is mounted on one ASIC, dark current (i.e., standby current) in a comparator circuit increases. Here, the dark current is consumption electric current or supply current in a sleep mode. Since one comparator circuit as a construction of the receiver executes a function at a standby mode and a function at a communication mode, current always flows in the comparator circuit in order to receive the signal at the standby mode. Thus, when multiple receivers are arranged so as to correspond to multiple channels, the standby current in multiple receivers increases.
(Patent literature No. 1) JP-A-2005-316209